West Nile Virus Mosquito Cases Rise Across Multiple US States

Multiple states across the U.S. are experiencing detections of West Nile Virus in mosquitoes during 2025, prompting public health officials to increase caution and implement mosquito control measures. In Montgomery County, Ohio, mosquitoes tested positive leading to scheduled spraying, though no human cases have been reported this year, while residents are advised to use EPA-approved repellents and protective clothing. Similarly, New Bedford, Massachusetts, detected mosquitoes carrying the virus twice in recent weeks, with ongoing spraying efforts and warnings that mosquito activity remains high until the first frost. Indiana has found West Nile-positive mosquito pools in several counties with no human cases reported yet, urging residents to prevent mosquito breeding and protect themselves. Rhode Island elevated its West Nile risk level from medium to high after multiple positive mosquito samples, with officials noting West Nile as the only mosquito-borne disease detected this year. In Pennsylvania, Lancaster County reported four human cases likely infected in summer months, alongside state recommendations for mosquito control and personal protection due to the lack of vaccines or treatments for West Nile Virus.